Tuesday, 28 February 2017

Nail wraps are flexible adhesive films that are smoothed onto the nail’s surface and trimmed.

They
provide an opportunity for intricate designs that can be printed by the
manufacturer that would otherwise be difficult to paint by hand. The design will be consistent across all nails and removes the difficulty of using the non-dominant hand to paint. Nail
wraps must have high initial adhesion to the nail to provide a manicure
that will last. If there are weak spots in the adhesive, an edge may
peel and the finish will not last. The adhesive strength of the wraps
can be tested using the TA.XTplus Texture Analyser. A higher adhesive strength and work of adhesion are generally desirable.

Figure 8: Multi-Hole Indexing Plate for the Adhesive Indexing System

A
simple test has been developed to measure the adhesive force, the work
of adhesion and the stringiness of the adhesive on the reverse side of
the wraps. To test for variation between or within samples, a large
number of tests is recommended. The Multi-Hole Indexing Plate (Figure 8)
by Stable Micro Systems enables ten tests to be made in quick
succession. Ten nail wraps are applied to the underside of the plate,
which is attached to an Adhesive Indexing System secured on the
instrument bed. A 7mm domical probe is brought into contact with the
wrap. A specific load is applied for 3 seconds.

Figure 9: Adhesive tests of
two different nail wrap samples

The
probe is quickly pulled away from the wrap during which time the
adhesion forces are measured. Graphs showing the adhesive force of two
different nail wrap samples are shown in Figure 9. The higher adhesive force of the black sample than the pink shows it is more suitable for this application.

We can design and manufacture probes or fixtures for the TA.XTplus texture analyser that are bespoke to your sample and its specific measurement.

Once
your measurement is performed, our expertise in its graphical
interpretation is unparalleled. Not only can we develop the most
suitable and accurate
method for the testing of your sample, but we can also prepare analysis
procedures that obtain the desired parameters from your curve and drop
them into a spreadsheet or report designed around your requirements.